MARQUETTE, Michigan (AP) — Two people in the US have been charged with threatening to sell photos of John Stamos unless he paid them $680,000.

Allison Coss and Scott Sippola were arrested last week on an extortion charge at an airport in Michigan. An undercover FBI agent had arranged to meet them there.

The FBI says it was contacted on November 28 by a lawyer for an actor identified in a court document only as "Mr. X."

Stamos spokesman Matt Polk said on Tuesday the photos simply are pictures of the actor posing with fans. He says the photos eventually will be released.